Automatic off-bearing assembly for dryers



Oct. 15, 1963 A. H. BECKLEY AUTOMATIC OFF-BEARING ASSEMBLY FOR DRYERS 5Sheets-Sheet 1 Filed NOV. 16, 1959 II/II/II/ff/f/Il/II! ll/llI/l/l/l/l/I'll/l/i/l/lf INVENTOR.

ATTORNEY Oct. 15, 1963 A. H. BECKLEY AUTOMATIC OFF-BEARING ASSEMBLY FORDRYERS 5 Sheets-Sheet 2 Filed Nov. 16, 1959//V///////////ll/l/I/lI/l/ll/I/l/l ATTORNEY Oct. 15, 1963 A. H. BECKLEYAUTOMATIC OFF-BEARING ASSEMBLY FOR DRYERS 5 Sheets-Sheet 5 Filed NOV.16, 1959 INV ENT OR.

ARTHU R H. B'ECKLEY ATTO R N EY Oct. 15, 1963 A. H. BECKLEY 3,107,017

AUTOMATIC OFF-BEARING ASSEMBLY FOR DRYERS Filed Nov. 16, 1959 5Sheets-Sheet 4 Ill IIIIIIIIII' H v INVENTOR.

ARTHUR H. BECKLEY TTORN EY United States Patent 3,197,017 AUTOMA'HQ(EFF-BEARING ASSEMBLY FOR DRYERS Arthur H. ecirley, Portland, Greg,assign'or to Moore Dry Kiln Company, North hoitland, Greg, a corporationof Gregon Filed Nov. 16, 1959, Ser. No. 353,285 2 Claims. (Ci.214--16.4)

This invention relates to the handling of such materials as sheets ofveneer as they are received from a dryer and are required to be placedconsecutively on a conveyor for delivery for further processing orhandling.

More specifically, the invention relates to the depositing of sheets ofveneer individually and consecutively onto a continuous conveyor as suchsheets are delivered from a multiple deck dryer and cooler.

Heretofore it has been customary to have such sheets of veneer, whendischarged from the dryer and cooler, placed manually on a continuousconveyor, one after the other, so that the sheets can be delivered tostations where the sheets are sorted and graded before being deliveredto storage.

The object of the present invention is to provide con tinuouslyoperating means by which the placing of the individual sheets from thedryer and cooler onto a continuous conveyor will be done mechanicallyinstead of manually.

A related object of the invention is to provide suitable means by whichthe sheets will be deposited directly onto the continuous conveyor asdelivered, instead of being deposited first onto a receiving platformand pile and then placed on the continuous conveyor.

Another object of the invention is to provide an offbearing assemblywhich will operate in conjunction with a multiple deck dryer and coolerso as to cause the sheets from the various decks to be delivered ontothe same conveyor.

A further object is to provide an automatic delivery control for thedecks of the multiple deck dryer and cooler whereby the sheets fromconsecutive decks will be discharged consecutively, and further to causeonly one sheet or sets of sheets at a time to be discharged from thedryer and cooler.

An additional object of the invention is to provide adjustable speedcontrol means for such automatic olfbearing assembly, operating incombination with a multiple deck dryer and cooler, whereby the speed atwhich the sheets are removed from the decks of the dryer and cooler canbe regulated by and coordinated with the speed at which the sheets arebeing delivered by the dryer and cooler, which in turn can be regulatedby the speed for which the dryer is set.

A still further specific object of the invention is to provide apractical tipple assembly through the medium of which veneer sheets froma multiple deck dryer and cooler can be quickly and automaticallytransferred individually to a continuous conveyor.

The manner in which these objects and other advantages are attained withthe present invention, and the manner in which the various parts of theoff-bearing assembly are caused to function, will be apparent from thefollowing description and explanation with reference to the accompanyingdrawings.

In the drawings:

FIG. 1A is a diagrammatic side elevation of a multiple deck off-bearinsection together with a connected end of the multiple deck dryer andcooler, showing also a portion of the adjacent or receiving end of themoving off-bearing tipple, the driving means for the feeder rolls forthe off-bearing section being indicated diagrammatically but the meansfor controlling the discharge of the 3, l Wfll'l Patented Get. 15, 1963'ice veneer sheets from the decks of the off-bearing section onto thetipple being omitted for the sake of clarity;

FIG. 1B is a continuation of FIG. 1A and is an elevation, partlydiagrammatic, of the olf-bearing tipple leading from the off-bearingsection to the endless conveyor;

FIG. 2 is a fragmentary side elevation, partly diagrammatic, of thelower portion of the discharging end of the multiple deck off-bearingsection together with a portion of the adjacent receiving end of thetipple, this view being taken from the side opposite that shown in FIG.1A and illustrating the means for controlling the discharging of theveneer sheets from the decks of the offbearing section, but omitting thedriving means for the feeding rolls in the off-bearing section;

FIG. 3 is a fragmentary plan View taken on line 33 of FIG. 2, showing aportion of the discharge control assembly, including pinch wheels and astop gate;

FIG. 4 is a corresponding perspective view of the same portion of thedischarge control assembly;

FIG. 5 is a fragmentary and foreshortened front elevation of the samelower portion of the discharging end of the multiple deck off-bearingsection taken on line 55 of FIG. 2;

FIG. 6 is a fragmentary section, taken on line 6-5 of FIG. 2, of one ofthe spring-mounted carriers for one of the pinch wheels, drawn to alarger scale;

FIG. 7 is a fragmentary plan view, taken on line 77 of FIG. 1A, of themechanically-operated switch means which is adjustably driven byconnection with the feed rolls of the dryer and cooler and which, inconjunction with time delay relay switches, produces the activation ofthe circuits to solenoid-operated valves, which control actuation of theair cylinders operating pinch wheels and stop gates for regulating thedischarge of the veneer sheets from the various decks of theoff-bearing.section, and the solenoid-operated valves for hydraulicoperating means for the off-bearing tipple;

FIG. 8 is a fragmentary sectional elevation taken on line 88 of FIG. 1B,but drawn to a larger scale; and showing part of the means controllingup and down movement of the tipple;

FIG. 9 is an enlarged fragmentary sectional elevation taken on line 99of FIG. 7; and

FIG. 10 is a simplified schematic wiring diagram to illustrate themanner in which the operation of the device is controlled andsynchronized.

Referring first to FIG. 1A, the reference 10 indicates the dischargingend of a six deck dryer and cooler, the decks of which dischargerespectively onto the corresponding decks 12, 13, 14, 15, 16 and 17, ofthe six deck ofibearing section 11. Each deck of the dryer and cooler 19is provided with driven feed rolls indicated by the broken lines 68 inFIG. 1A. Each deck of the oif-bearing section 11 similarly is providedwith driven feed rolls which are connected by endless drive chains 18,19, 20, 21, 22 and 23 respectively to the forward end rolls 24, 25, 26,27, 28 and 29 respectively, these end rolls in turn being connectedtogether by a series of endless chains St A drive sprocket 31 for theend roll 24 is driven by an endless chain connection 32 with a sprocketmounted on a bottom delivery roll 33, and the delivery roll 33 is drivenby an endless chain connection 39 with a motor M. Pairs of deliveryrolls 33 and 33, 34 and 34, 35 and 35, 36 and 36, 37 and 37', and 38 and38', are mounted at the discharge ends of the six decks of theoff-bearing section respectively. The pair of delivery rolls 33 and 33'on the lowest deck of the off-bearing section are connected by anendless chain 40, and the delivery rolls in each of the other pairs aresimilarly connected together. The rolls 33, 34, 35, 36, 37 and 38 areconnected together by a series of endless chains, as indicated. Thus allthe delivery rolls are driven in unison by the motor M, and all theseries of feed rolls likewise are driven in unison by the same motor,but the delivery rolls are driven at greater speed than the feed rolls,as apparent from FIG. 1A. The sheets of veneer are moved along by thefeed rolls on the various decks of the off-bearing section 11 (from leftto right as viewed in FIG. 1A) until they reach the more rapidlyrotating set of delivery rolls. As each sheet reaches the delivery rollson its deck it is temporarily restrained, by a stop fence hereinafterdescribed, until the adjacent end of the moving transfer assembly 41,commonly known as a tipple, comes into registration with that deck,whereupon the stop fence is raised and the delivery rolls, with theassistance of cooperating pinch wheels later described, cause the sheetof veneer to be discharged quickly and positively onto the tipple.

Referring now to FIG. 1B, the tipple 41 includes a frame 42 which ispivotally supported at its discharge end on a supporting structure 43and is swingable up and down on a horizontal axis. The tipple frame 42is also supported on a pair of hydraulic pistons and piston rods 44 (seealso FIG. 8) which move up and down in hydraulic cylinders 44, thecylinders being pivotally mounted on suitable base supports.

The two pistons are operated in unison, the hydraulic fluid beingdelivered into and withdrawn from opposite ends of the cylinders 44'through conduits under the control of suitable solenoid-operated valvesand the conduits are connected with a pump assembly operated by a motorM2 (FIG. 1B). The pump, valves, and controls for this hydraulic assemblyare of well-known design and need not be described in detail since theydo not constitute part of the present invention. The entire hydraulicassembly is so arranged and so controlled by automatic but adjustableswitch means that the hydraulic pistons move the tipple from itslowermost position (in registration with the bottom deck 12 of theoff-bearing section 11) to its highest position (registration with thetop deck 17 of the off-bearing section 11) in a series of five movesoccurring during equal periods of time, and then return the receivingend of the tipple from its highest position to its lowermost positionquickly during a single equal period of time.

The delivery of the sheets of veneer from the respective decks of theoff-bearing section 11 occurs during the upward travel of the receivingend of the tipple only. This feature of having the downward movement ofone end of a tipple take place at a greater speed than the upwardmovement, with downward movement occurring entirely within the sameamount of time required for the tipple to move upwardly from one deck orstation to another, has been employed in other devices and consequentlyis not new in itself.

In order to maintain the up and down movement of the tipple exactly thesame at both sides of the tipple, and thus to prevent the possibility ofany slight tipping of the tipple towards one side or the other, whichmight be occasioned by a tendency for'one hydraulic piston to move atslightly different speed from the other or over a slightly differentdistance, a pair of identical rack bars 45 (FIGS 1B and 8) have theirupper ends pivotally attached to the tipple frame 42 at opposite sides.These rack bars move up and down in guideways in constant engagementrespectively with a pair of identical pinions 46 (one of which is shownin FIG. 8) which pinions are secured on a common rotatably supportedshaft 47.

The tipple is provided with a series of feed rolls 48 (FIG. 1B) whichare joined at their ends by drive chains 49 and thus rotate in unison,and these are driven by chain or belt connection with the driving shaftof a motor M3. Pivotally supported press rolls 50 are arranged so as torest on some of these feed rolls 48 and thus to bear on the veneersheets which move along over the feed rolls 4% in order to keep theveneer sheets on the tipple moving at the desired speed for which themotor M3 is set. The pivotally mounted or discharging end of the tipple,thus the right hand end as viewed in FIG. 1B), discharges onto anendless traveling conveyor C. The conveyor C is driven by suitable means(not shown) and at suitable speed with respect to the operation of thetipple and its feed rolls, so that the veneer sheets delivered from thedischarging end of the tipple will be deposited on the conveyorseparated from such other and arranged in consecutive order.

The means by which the delivery of the sheets of veneer from theseparate decks of the off-bearing section 11 onto the receiving end ofthe tipple 41 is automatically controlled will now be described withreference to FIGS. 2, 3, 4 and 5. As previously explained with referenceto FIG. 1A, a pair of more rapidly driven delivery rolls are locatedconsecutively along the discharging end of each of the decks of theelf-bearing section 11. Thus the delivery rolls 33 and 33' are locatedconsecutively at the discharging end of the lowest deck 12; the deliveryrolls 34 and 34 are located at the discharging end of the deck 13; andso on. Pinch wheels are provided for the purpose of bearing down on thefirst delivery roll of each pair, and thus on the rolls 33, 34, etc., soas to cause the veneer sheet, which has been moved into position betweensuch delivery roll and its cooperating pinch wheels, to be thrustforwardly and discharged from the off-bearing section 11 onto the tippleat the proper time. Since similar pinch wheels are provided for each ofthe delivery rolls 33, 34, etc., it will be sufficient to describe themounting and manner of operation of the pinch wheels for the deliveryroll 33 on the bottom deck of the elf-bearing section.

A shaft 51 (FIGS. 3, 4 and 5) is rotatably mounted in the frame of theofi-bearing section 11 parallel to and near to the roll 33 and above thepath of the veneer sheets passing over the roll 33. Pairs of parallelbrackets 52 (shown best in FIGS. 3 and 4) are carried by the shaft 51. Apinch wheel carriage 53 is pivotally mounted at one end on a pin 54carried by each pair of brackets 52. A lower pin 55 limits the downwardswing of the wheel carriage 53. A pinch wheel 56 is supported in theopposite or free end of the carriage 53. A bar 57 (see FIG. 6) extendsupwardly from the middle of the pin 55 through an aperture in a crossweb 53' of the carriage 53. The upper end of this bar 57 is threaded andcarries an adjustable nut 58. A coil spring 59 is carried on the bar 57and is held under compression between the cross web 5 3 and the nut 58.

A pair of arms 60, secured to the end of the shaft 51, have a pivotalconnection with a piston rod 61 which is operated by an air cylinder 62.Consequently, as apparent from FIGS. 2 and 4, movement of the piston rod61 outwardly with respect to its cylinder 62 will cause the pinch wheels56 to be moved downwardly against the delivery roll 33, while movementof the piston rod 61 in the opposite direction will lift the pinchWheels 56 above the delivery roll 33.

A fence shaft 63 is rotatably mounted in the frame of the off-bearingsection 11 beyond the pinch wheel assembly and is connected by suitablelink arms with the pinch assembly shaft 51 so as to be rotated with thepinch assembly shaft. An elongated narrow plate or stop fence 64 issecured to the shaft 63. As shown best in FIGS. 2 and 4, the arrangementis such that movement of a piston rod 61 to bring the pinch wheels 56downwardly upon the delivery roll 3-3 will cause the stop fence 64 to beswung out into inoperative position; whereas movement of the piston rod61 in the opposite direction will result in raising the pinch wheelsfrom the delivery roll and in lowering the stop fence 64 into positionfor blocking the discharge of'a veneer sheet from that particular deckto the off-bearing section 11.

Thus when the receiving end of the tipple 41 is moved down into properposition for receiving a veneer sheet from the bottom deck ofoff-bearing section, for example, the delivery of compressed air intoone end of cylinder 62, forcing the piston rod =51 outwardly, will causethe pinch wheels 56 to bear down on the veneer sheet as it rides on theroll 33 and result in the driving of the sheet rapidly forwardly, whilethe raising of the stop fence 64 at the same time allows the freepassage of the veneer sheet from the deck of the off-bearing sectiononto the tipple. The delivery of compressed air to the opposite end ofthe cylinder causes the fence 64 to be lowered and the pinch wheels 56to be raised. The stop fence 64- is in the lowered normal blockingposition and the pinch wheels are in the raised inoperative position atall times except during the moment in which the sheet or sheets fromthat deck is to be discharged onto the tipple. Consequently a sheet ofveneer or sheets of veneer which have reached the delivery roll 33 andits forward companion delivery roll 33' will temporarily be held in thislocation until the proper time for discharge onto the tipple. for eachpinch wheel carriage enables the pinch wheels to press down with adesired amount of resilient force on the sheet of veneer which theyengage when the sheet is to be discharged from the chi-bearing sectionwith the lifting of the stop fence.

The same combination of delivery rolls, pinch wheels, and stop fence isprovided similarly for each deck of the off-bearing section 11. In orderto enable these actuating mechanisms to be more compactly arranged atthe side of the cooler the air cylinders and pinch wheel assemblies aresomewhat differently positioned for alternate decks of the cooler, buttheir manner of operation is the same for each deck. Thus it will beobserved from FIG. 2 that the cylinder 62 and the pinch wheel assemblyshaft 51 for the next deck 13 are in relatively different locations fromthe locations of the cylinder 62 and pinch wheel assembly shaft 51 forthe deck 12, but this is merely for convenience in arrangement. Due tothe resulting spacing between the pinch wheel assembly shaft 51 and thefence shaft 63' for the deck 12, additional linkage is interposedbetween the two. For the deck v14 the arrangement is the same as for thefirst deck 12, and so on. While the air cylinders and the otheroperating mechanism for the pinch wheel assemblies and fence shafts areillustrated only on one side of the off-bearing section 11, preferablythese are also provided at the opposite side of the off-bearing sectionas well, since the width of the dryer and the off-bearing section inmost instances would make this desirable. Similarly, although thedriving means for the feed rolls and delivery rolls are shown on onlyone side of the off-bearing section 11, for the sake of clarity, it isto be understood that such driving means are provided also at theopposite side.

The speed of operation of the entire device is automatically governed bythe speed of the dryer and cooler, and the latter is regulated in thecustomary manner (not shown) with regard to the length and nature of theveneer sheets being handled, etc. An adjustable gear drive, located in ahousing 65 mounted on one side of the offbean'ng section 11 (FIGS. 1Aand 7), is driven by belt connections 65 and s7 from one of the drivenfeed rolls 63 of the dryer and cooler .10. A shaft 69 FIG. 7), rotatedthrough the intermediary of the adjustable gear drive in the housing 65,carries a pair of cam discs 70 and 71 each of which has six equallyspaced cam lobes (corresponding to the number of decks in theoff-bearing section) which engage a contact element 72 or 73 upon therotation of the cam disc. The discs are so arranged that their cam lobesare staggered with respect to each other. When the contact element 73for the cam disc 71, for example, is connected through a suitable timedelay relay to the circuits for the relays and solenoids controlling theactuation of the air cylinders which operate the stop fences and pinchwheels on the decks of the offbearing section and for the relays andsolenoids for the The adjustable coil spring 59 hydraulic valvescontrolling the movements of the tipple, the successive engagement ofthe contact element 73 by the 6 cam lobes on the disc 71 during onerevolution of the disc 71 will complete a cycle of operation of thedevice for the corresponding 6 decks of the off-bearing section with theproper timing for veneer sheets of a particular length, thus for sheetsof the customary length of eight feet. However, if veneer sheets havinga length of only four feet are to be handled in the device, then thecontact element 72 for the other disc 76 is also connected into the samecircuits, and, since the cam lobes on the two discs 71 and 70 arestaggered with respect to each other, the connecting of the contact 72as well as the contact 73 into the operating circuits and the adjustmentof the time delay relay will double the speed of operation of the deviceby reducing the discharging period for the different decks by one-half,thus enabling the device to operate with full ef iciency for four footveneer sheets. Furthermore, by adjusting the hand wheel 74 (FIG. 7) ofthe ratio adjustment of the adjustable gear drive for the shaft 69,intermediate and further variations in the timing periods and thus inthe speed of operation of the device are attainable to correspond toother lengths of veneer sheets, should the veneer sheets which are beingput through the dryer be of some other length.

During any single period of operation of the veneer dryer and cooler,and thus of the off-bearing section, the veneer sheets will all be ofthe same length, the speed of operation of the dryer and cooler and thetiming of the operation of the fences and pinch rolls in the off-bearingsection and of the movements or" the tipple being adjusted for theparticular length of the sheets as previously indicated. However, whilethe sheets will all be the same length their widths may varyconsiderably. In order to prevent the possibility of any sheetsdeviating towards one side or the other from their course through theoff-bearing section a plurality of small guide wheels 76 (FIG. 1A) areprovided on each deck of the oil-bearing section. These wheels aremounted on pivoted arms 75 and ride on the feed rolls except whenengaged by the veneer sheets. The guide wheels are spaced a shortdistance apart transversely with respect to the forward direction oftravel of the sheets and thus a guide wheel would engage the side edgeof any sheet which attempted to turn towards one side.

A bar 84 (FIG. 1B), attached to the frame 42 of the tipple 41, supportsa carriage 83 which slides up and down in a guideway '85 with the up anddown movement of the tipple. The carriage 83 has a member 83' whichengages actuating elements for switch assemblies arranged in asuccession of six switch boxes 77", 78', 79', S43", 81 and 82" sopositioned that the travel of the moving or receiving end of the tippleintermittently from the lowest deck 12 to the top deck 17 (FIG. 1A) ofthe offbearing section :11 will cause the switch assemblies to beengaged respectively. The controlled movement of the tipple 41 is suchthat when the tipple is in its lowest position, thus receiving theveneer sheet or sheets from the bottom deck 12 of the off-bearingsection 11, the member 83' will be in engagement with the actuatingelement in the lowest switch box 77 The tipple remains in this positionfor a predetermined period of time during which the stop fence for thedischarging end of the lowest deck 12 of the off-bearing section israised and the pinch wheels for that deck are lowered, such period oftime being sulficient to allow the sheet or sheets of veneer from theend of the deck 12 to be discharged onto the tipple. Then the tipplemoves quickly up to the next deck of the offbearing section and remainsat the next deck for the same predetermined period, the member 83' thenengaging the actuating element in the next switch box 78", and so on.When the tipple arrives at the top deck it remains there for the samepredetermined period, with the member 83' engaging the actuating elementin the switch box 82". The tipple next moves rapidly all the way down toits lowest position, moving five times as fast as during each of itsupward movements.

The actuation of the solenoids for the hydraulic valves governing themovement of the tipple, the actuation of the solenoids forv the airvalves controlling the air cylinders and pistons which operate the stopfences and pinch wheels on the corresponding decks of the off-bearingsec tion, and'the connected time delay elements all functionautomatically in accordance with the speed at which the entire device isset to operate, and the speed in turn is governed by such conditions asthe speed of the dryer and cooler and the length of the veneer sheetsbeing handled, as previously mentioned.

The manner in which the operations are coordinated and automaticallycontrolled can be explained briefly and more clearly with reference tothe special schematic diagram of FIG. 10. In this schematic diagram allunimportant wiring details have been omitted for the sake of simplicityand clarity.

In FIG. 10, in which L1 and L2 are the two power line conductors, thesolenoids for the air valves for the air cylinders operating the stopfences and pinch wheels on the six decks of the off-bearing section areindicated at 1'2, 13, 14', 15, 16' and :17 respectively. In describingthe operation it is assumed first that the device is being used forveneer sheets of the standard length of eight feet. It is assumed alsoat the start that the tipple is in registration with the bottom deck 12,as indicated in FIG. 1A and FIG. 2. In this position of the tipple theengagement of the member 83' (FIG. 1B) with the element in the switchbox 77" causes the switch 77 (FIG. to be opened and its companionrelated switch 7 7 to be closed. The time switch contacts 112 and 1113for the cam disc 71 (FIG. 7) are manually set and closed. With therotation of cam disc 71 the engagement of any one of its six cam lobeswith the contact element closes the contact (indicated by the switch 73in FIG. 10) .momentarily. This activates the time delay relay 86 whichoperates to close the time switch 87. The activation of 86 momentarilyalso closes switch 88, activating time delay switch 89 through thenormally closed switch 98 and the previously manually closed time switch113. Activation of 89 closes the holding circuit switch 90 and inaddition closes switch 91. The closing of switch 91 momentarily causescurrent to pass through the by-pass line to the control relay 93 throughthe normally closed switch 92. The control relay 93 operates to closeholding switch 94 and switch 95. Switch 95 causes activation of solenoid96 through the normally closed switch 1107. Solenoid 96 operates a valvein the hydraulic system for the tipple which starts the tipple movingupwardly. Switch 95 is connected with by-pass switch 92 so that theclosing of switch 95 opens by-pass switch 92. Since the switch 77returns to its normal closed position immediately the tipple startsmoving upwardly, the circuit to control relay 93 momentarily remainsclosed and thus holds switch 95 closed and solenoid 96 remains activatedwith the tipple moving upwardly. The closing of switch 95 activates thetime delay element -97 to hold switch 92 open. The activation of relay93 also opens switch 98 thereupon rendering switch 89 inactive whichopens switches 90' and 91 and causes switch 89 to be reset for the nextcycle. When the tipple reaches the second deck 13 the switch 78 isopened and the related switch 78' is closed. The opening of switch 78interrupts the circuit to control relay 93 which opens switches 94 and95, allows switches 92 and 98 to close, and deactivates solenoid 96,causing the tipple to stop its upward movement. The opening of switch 78causes the closing of the related switch element 7 8' and the activationof solenoid 13' which opens the stop gate and lowers the pinch wheels onthe second deck 13 of the oft-bearing section.

This cycle of switch operations is repeated five times as the tipplemoves upward in intermittent periods, each cycle being caused by theclosing of the contact 73 by the engagement of the cam lobe on the disc71 with its contact.

When the tipple reaches the top deck and opens switch 32 and closes thecompanion switch 82', activating solenoid 17 and causing the veneersheet from the top deck 17 to be delivered onto the tipple, the openingof switch 82 closes a connected switch 82A which activates control relay99. This relay 99 closes switch 101. The activation of current relay 93through by-pass switch 92 closes switch .102, and, since switch .101 isclosed the relay 103 is now activated. This relay opens switch 107 andcloses switch 105. Switch 105 activates solenoid 106 which produces thedownward movement of the tipple. The relay 103 also closes the holdingcircuit switch 104. When the tipple reaches the lower deck 12 the switch77 is opened and the next cycle starts. Manual control switches areindicated at 120 and 108.

If four foot sheets are now to be handled in place of eight foot sheetsthe circuit will be closed through the switch 72 as well as through theswitch 73. In other words both discs 70 and 71 (FIG. 7) will govern thetime period cycle. Manual switch 72' is closed to enable the closing ofswitch '72 by its disc to become effective. The time delay relayswitches 114 and .116 are also manually closed at the same time thusenabling time delay relays 115 and 117 to function in the same manner asthe time delay relays I112 and 113 previously mentioned. Now time delayrelay 1'15 operates to close switch 87 and switch 115, and time delayrelay .1 17 operates the holding switch 109 and switch 111. Theoperation throughout the cycle is as previously described but since eachcycle occurs alternately by the closing of the contacts for both camdiscs with their cam lobes staggered, and thus by the alternate closingof switches 73 and 72 as illustrated in FIG. 10', the cycles take placetwice as rapidly, and consequently the entire device is speeded up so asto handle veneer sheets of four feet in length instead of eight feet inlength with similar efiiciency.

As previously indicated, the cycles of operation can be varied furtherby adjusting the adjustable gear drive connection by which the discshaft 69 is driven from the driving rolls of the dryer and cooler. Thusthe entire elf-bearing assembly including the off-bearing section 11 andthe moving tipple can be adjustably set to operate automatically at thespeed desired with respect to the speed of the dryer and cooler and thelength of the veneer sheets being handled, and the sheets will bedelivered at the desired rate, separately and consecutively, onto thecontinuous moving conveyor C.

While the device has been illustrated and described for use with a sixdeck dryer and cooler, and thus with the off-bearing section of thedevice providing the corresponding six decks, it is of course to beunderstood that the actual number of decks may be varied.

I claim: a

1. In equipment for unloading sheets of material from a multiple deckconveyor assembly of the character described, control elements on thedischarge end of each deck of the conveyor assembly for controlling thedischarge of material from such assembly deck, said discharge controlelements for each deck including a rotating delivery roll, pinch wheelspositioned above said delivery roll, a stop fence located beyond saidpinch wheels and delivery roll in the direction of travel of material onthe deck, and means for moving said pinch wheels downwardly towards andupwardly from said delivery roll and for raising and lowering said stopfence, a switch assem bly for each deck controlling the operation ofsaid means, a tipple pivotally mounted at its discharging end on a fixedsupport and having a receiving end movable up and down into registrationsuccessively with the discharge ends of the conveyor decks, switchactuating means carried by said tipple, cooperating switches connectedrespectively with said switch assemblies on the decks of the multipledeck conveyor, said cooperating switches positioned for engagementseparately by said switch actuating means as said receiving end of saidtipple moves intoregistration with each corresponding deck, whereby saidswitch assembly for each deck will be operated to move the controlelements for that deck into discharging position when said receiving endof said tipple is in registration with that deck, means forautomatically moving said receiving end of said tipple up and down, andmeans controlling the speed of operation of said tipple moving means.

2. In equipment for unloading sheets of material from a multiple deckconveyor assembly, control elements on the discharge end of each deck ofthe conveyor assembly for controlling the discharge of material from thedeck, means on each deck for operating said discharge control elementsfor that deck, a switch assembly for each deck controlling the operationof said means, a tipple pivotaliy mounted at its discharging end on afixed support and having a receiving end movable up and down intoregistration successively with the discharge ends of the decks, switchactuating means carried by said tipple, cooperating switches connectedrespectively with said switch assemblies on the decks of the multipledeck conveyor, said cooperating switches positioned for engagementseparately down, and adjustable means controlling the speed of operationof said tipple moving means.

References Cited in the file of this patent UNITED STATES PATENTS 71,809,456 Streeter June 9, 1931 1,959,662 Ellis May 22, 1934 2,055,805Rapisarda Sept. 29, 1936 2,599,693 Chapman June 10, 1952 2,649,182Parker Aug. 18, 1953 2,876,009 Jeddeloh Mar. 3, 1959 2,921,663 ParkerJan. 19 1960 Canada June 3, 1958

1. IN EQUIPMENT FOR UNLOADING SHEETS OF MATERIAL FROM A MULTIPLE DECKASSEMBLY OF THE CHARACTER DESCRIBED, CONTROL ELEMENTS ON THE DISCHARGEEND OF EACH DECK OF THE CONVEYOR ASSEMBLY FOR CNTROLLING THE DISCHARGEOF MATERIAL FROM SUCH ASSEMBLY DECK, SAID DISCHARGE CONTROL ELEMENTS FOREACH DECK INCLUDING A ROTATING DELIVERY ROLL, PINCH WHEELS POSITIONEDABOVE SAID DELIVERY ROLL, A STOP FENCE LOCATED BEYOND SAID PINCH WHEELSAND DELIVERY ROLL IN THE DIRECTION OF TRAVEL OF MATERIAL ON THE DECK,AND MEANS FOR MOVING SAID PINCH WHEELS DOWNWARDLY TOWARDS AND UPWARDLYFROM SAID DELIVERY ROLL AND FOR RAISING AND LOWERING SAID STOP FENCE, ASWITCH ASSEMBLY FOR EACH DECK CONTROLLING THE OPERATION OF SAID MEANS, ATIPPLE PIVOTALLY MOUNTED AT ITS DISCHARGING END ON A FIXED SUPPORT ANDHAVING A RECEIVING END MOVABLE UP AND DOWN INTO REGISTRATIONSUCCESSIVELY WITH THE DISCHARGE ENDS OF THE CONVEYOR DECKS, SWITCHACTUATING MEANS CARRIED BY SAID TRIPPLE, COOPERATING SWITCHES CONNECTEDRESPECTIVELY WITH SAID SWITCH ASSEMBLIES ON THE DECKS OF THE MULTIPLEDECK CONVEYOR, SAID COOPERATING SWITCHES POSITIONED FOR ENGAGEMENTSEPARATELY BY SAID SWITCH ACTUATING MEANS AS SAID RECEIVING END OF SAIDTIPPLE MOVES INTO REGISTRATION